The invention relates generally to user interfaces. More specifically, the invention relates to a user interface for a forensic video search. Further, the invention relates to the query processing in response to the user interface for a forensic video search.
An increasing need for enhanced site security and safety has fueled a rapid expansion of video camera network installations worldwide. In the United Kingdom alone, as of 2006, it is estimated that there were more than 4.2 million CCTV cameras with over 500,000 installed just in London. Camera networks such as these, often operating 24 hours a day and seven days a week, generate massive amounts of image and video surveillance data.
A vast majority of the data is typically archived for later analysis in case of disruptive events. Often, time-critical information needs to be extracted from the archived surveillance video to aid an ongoing investigation, or to prevent further security breaches or safety infractions. However, due to the sheer volume of data that is acquired and stored, effectively searching through it for interesting events, in a timely manner, becomes an extremely challenging task. Therefore, the amount of data acquired by visual surveillance devices far exceeds the operator's capacity to understand its contents and meaningfully search through it. This represents a fundamental bottleneck in the security and safety infrastructure, and has prevented video surveillance technology from reaching its true potential.
Automated video analytic modules provide one means of addressing this problem by analyzing the contents of a video feed and generating a description of interesting events transpiring in the scene. Video Content Analysis (VCA) modules can be set up for real-time analysis of the video stream to generate alarms as specific events occur. Alternatively, they can also be used to generate, what is referred to as, event metadata that is stored offline in a database. The event metadata database can be searched through and can be used to index the original recorded video.
VCA modules operating in real-time typically analyze only a single camera video stream and capture events in a camera's field of view or scene. It is often the case that detection of complex interesting events requires an examination of events that transpired across multiple cameras that occur over large spans of time, involving multiple actors and objects. Such in-depth analysis has typically required human operator involvement to piece together a big picture from smaller pieces of evidence.
What is desired is a user interface that facilitates the forensic search of complex global events that are composed of a number of simpler, low complexity events.